Directed by: Bruce Robinson
Starring: Richard E. Grant, Richard Griffiths, Ralph Brown, Paul McGann
Factual error: When they are driving back home from the holiday cottage you can clearly see an M25 sign in the background. The M25 didn't exist in the 60s.
Factual error: The roadsigns on the motorway are quite contemporary (1980's), the signs used in the 1960's would have looked considerably different. To travel to Penrith, Withnail & I would have had to leave London via the A1, and not the M25 motorway, which wasn't constructed until many years later.
Continuity mistake: When Monty drives Withnail & I into Penrith the radish is on his left lapel. When they arrive in Penrith a few minutes later, the radish has mysteriously moved to his right lapel.
Barman: Time, gents, please.
Withnail: Alright, we're going to have to work quickly. A pair of quadruple whiskies and another pair of pints, please.
Trivia: The lighter fluid scene was based on a real incident. Writer/ director, Bruce Robinson and actor Gregory Floy have both said that Vivian MacKerrell, the principal inspiration for Withnail, really did once drink lighter fluid. Gregory Floy also said that he walked round Regents Park in the pouring rain with Vivian, when he was due to go to the US for 6 months to appear in a play. Vivian was about to leave London and return to Nottingham and that it was very like the film's ending.
Question: At the pub in London, on Marwood returning from the toilet and saying "balls to Monty", Withnail says he's just spent an hour on the phone to Monty "flattering the bugger"? Surely Marwood wasn't in there for an hour and it's unlikely Withnail would have had time to phone Monty in the short while he surely must really have been in there, especially with a threatening guy sitting outside and likely to come in the longer he spent there.
Answer: I think he (Withnail) is just exaggerating about his "dedication" in completing Marwood's request.